Yavin IV - Star, Planet, or Moon?

I always believed that Yavin IV was the Earth sized moon of the gas giant planet Yavin that orbited a star that was never named in the movie.

But what are the possibilities?

1) Yavin was the name of the star and Yavin IV was the designation of the gas giant planet and Yavin IV something would have been the designation of the moon of Yavin.

Astronomers usually name extra solar planets orbiting other stars by the designation of the star followed by lower case Latin letter starting with b, c, d, etc. in the order of discovery. So the suspected planets of Alpha Centauri B are Alpha Centauri Bb and Alpha Centauri Bc.

According to the astronomical system used for planets of other stars, the planets in our solar system might be lettered in order of distance from the sun since the ones out to Saturn were known since ancient times and the others were discovered in order of distance from the sun. Thus it would be Mercury Sol b, Venus Sol c, Earth Sol d, Mars Sol e, Jupiter Sol f, Saturn Sol g, Uranus Sol h, and Neptune Sol i.

Astronomers designate the moons of planets in our solar both by proper names and also by the name of the planet followed by a Roman numeral in order of the moon's discovery. So Amalthea is also Jupiter V.

In science fiction extra solar planets are usually known by proper names given by humans and/or natives and also by the science fiction planet numbering system. In the science fiction numbering system planets are known by the human or alien name or other designation of the star followed by a Roman numeral in order of the distance from the star.

For example, in the Lensman series the planet Thralle is Trallis III and the planet Onlo is Trallis VIII if I remember correctly. In science fiction stories the planets in our solar system are often given as: Mercury Sol I, Venus Sol II, Earth Sol III, Mars Sol IV, Jupiter Sol V, Saturn Sol VI. Uranus Sol VII, Neptune Sol VIII, and Pluto used to be called Sol IX.

So according to the science fiction system the name of the star would be Yavin, the gas giant planet would be Yavin IV, and the moon of Yavin would have a proper name and an designation of Yavin IV something - but neither were given; it as just called the moon of Yavin. Certainly nobody used the name given to it by the people who built the temple thousands of years ago.

2) The name of the star is unknown, the planet is named Yavin, and the moon is designated as Yavin IV.

Astronomers designate the moons of planets in our solar both by proper names and by the name of the planet followed by a Roman numeral in order of the moon's discovery. So Amalthea is also Jupiter V.

According the system used by Earth astronomers to designate the moons of planets in our solar system, the fourth discovered moon of Yavin would be Yavin IV.

But maybe the explorers of that solar system discovered all the moons of Yavin at about the same time and numbered them in order of size or distance from Yavin. And nobody used the name given to it by the people that built the temple thousands of years ago.

3) Most stars are only designated by their numbers in star catalogs. Some stars are only listed in one star catalog, others are listed in many catalogs and thus have many designations, and and the vast majority of stars have never been cataloged.

So most star designations consist of either the full name of the catalog or else some abbreviation of the catalog followed by the catalog number for that star.

Thus a list of the nearest stars to Earth includes star catalog designations like: Luhman 16, WISE 1049-5319, Wolf 359, Lalande 21185, Luyten 276-8, Ross 154, Ross 248, Lacaille 9352, Ross 128, Struve 2398, Groombridge 34, Kruger 60, etc. etc.

So maybe the Star Wars galaxy has a Yavin star catalog and the star is listed as Yavin IV and the designations or names of the planet and the moon are unknown, even though the people who built the temple on the moon must have had a name for it.

Wookipedia says:

Yavin 4 was the jungle-covered fourth moon in orbit around the red gas giant Yavin. At some point during the Galactic Civil War, it hosted the headquarters of the Alliance to Restore the Republic, a group of resistance fighters that opposed the dominant Galactic Empire.[2] Following a major battle that took place around Yavin,[4] the Alliance relocated its headquarters to Hoth.[7]